The truth is that no one really knows how many Android tablets have been sold so far. Although, John Gruber of the Daring Fireball blog seems to have figured out a way to compute an estimated number. Gruber reckons that there are only about 1.21 million Android tablets actually in use around the world. Gruber bases his calculation on data from Android Market statistics and Larry Page’s announcements at a recent conference.

Google tracks devices accessing the Android Market according to screen size (among other device characteristics), and “xlarge” is registered in Google’s tracking system whenever a device having at least a 7-inch screen is used to access the Market. According to Google’s statistics, only 0.9% of “Xlarge” Android devices–that is, Android devices that have 7-inch screens or larger–have accessed the Android Market in the 7 days prior to July 1, 2011.

At Google’s quarterly analysts conference held last week, Google CEO Larry Page mentioned that the approximate number of total Android devices in use is 130 million.

Given the approximate total announced by Page, as well as the access statistics from the Android Market, and following Gruber’s reckoning, only 1.17 million devices indeed comprise the whole population of Android tablets.

Granting that the 0.9% tablet-based access to the Android Market in the 7-day period reflects a fairly accurate average percentage of the total tablet population, 1.17 million is a rather microscopic amount compared to the overwhelming majority of Android phones. If anything, in the world of Android, phones still outsell tablets.

Gruber’s estimate, though, seems to have ignored some other circumstances that could alter his approximation. For instance, it is possible that there is still a significant number of tablets that did not access–or could not access–the Android Market within the 7-day period.

There also possibly is a significant number of non-Honeycomb tablets/slates running Android 2.2 Froyo that were not counted as having “xlarge” screens because the “xlarge” size qualifier seems to have been introduced starting with Android 2.3 Gingerbread onwards. The list of non-Honeycomb tablets, slates, portable media players, and mobile Internet devices that had Android 2.2 Froyo or lower at launch time seems a bit long, although we have no data at all about the actual sales figures for those devices.

Even if we wiggle upwards a bit with Gruber’s estimated figures for Android tablets, Apple’s iPad still clearly dominates the tablet market, with reported sales–actual sales, not shipments–of about 28.73 million iPads sold from April, 2010 up to June, 2011.

Does this mean the iPad is the better tablet? Maybe. Maybe not. All that the statistics say is that the iPad sells more than Android tablets. The statistics hardly make judgments or subjective evaluations as to which device is better. The statistics clearly say, however, that Android tablets are running far behind the iPad, albeit for the time being, in terms of sales.

Does this mean that Android tablets won’t be able to catch up with the iPad in terms of sales? Definitely no. The statistics only clearly say that Android needs to catch up. The numbers don’t issue any judgment about Android’s potential to outsell the iPad.

What about you? Do you think Android tablets will ever gain traction and attention? Why do you think are Android tablets not selling as highly as the iPad?